Image forming apparatus

Abstract

To provide an image forming apparatus that enables alignment between housings with a simple configuration. [Solution] Positioning members 170a and 170b are provided on the housing 150A of the paper feed device 150, and positioning shafts 50a and 50b are provided on the housing 100A of the device body 100. The positioning shafts 50a and 50b enter and fit into the positioning members 170a and 170b as the device body 100 is slid into the paper feed device 150, in relation to the direction in which the device body 100 is attached to the paper feed device 150. The positioning shafts 50a and 50b fit into the positioning members 170a and 170b, thereby aligning the housing 100A and the housing 150A. When attaching the device body 100 to the paper feed device 150, the operator can temporarily place the device body 100 on the paper feed device 150, and then slide the device body 100 onto the paper feed device 150 while it is temporarily placed, thereby aligning the housing 100A and the housing 150A.

Description

Technical Field

[0001] The present invention relates to an image forming apparatus such as a printer, a copier, a facsimile machine, or a multifunction machine.

Background Art

[0002] In an image forming apparatus that forms an image on a recording material, a configuration has been proposed in which a plurality of housings in which various units are installed are stacked vertically. A series of operations related to image formation of the recording material are realized by various units installed in each of the plurality of housings. For example, below an image forming apparatus main body (hereinafter simply referred to as the apparatus main body) having a housing in which an image forming unit for forming an image on a recording material is installed, a cassette that houses the recording material and a feeding unit that supplies the recording material of the cassette to the apparatus main body, etc. A paper feeding device having another housing in which is installed is connected.

[0003] In order for an operator to attach the paper feeding device to the apparatus main body, the operator lifts the apparatus main body onto the paper feeding device. At that time, the operator arranges the housing of the apparatus main body and the housing of the paper feeding device in a predetermined relative position. Therefore, positioning holes and positioning pins are provided in the housing of the apparatus main body and the housing of the paper feeding device, respectively. Patent Document 1 discloses a paper feeding device further provided with a positioning auxiliary member. As the lifted apparatus main body is lowered onto the paper feeding device from above, the positioning auxiliary member guides the lower end frame so that the positioning hole provided in the lower end frame of the apparatus main body fits with the positioning pin provided in the upper end frame of the paper feeding device.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, even when the above-mentioned positioning assist member is used, the operator still has to lower the lifted device body from above to the paper feed device below, while simultaneously aligning the horizontal position of the device body housing with the paper feed device housing. Therefore, with conventional technology, it was difficult to connect multiple housings at predetermined relative positions.

[0006] The present invention has been made in view of the above problems, and aims to provide an image forming apparatus that enables an operator to easily align the housings of the housings. [Means for solving the problem]

[0007] An image forming apparatus according to one embodiment of the present invention is an image forming apparatus for forming an image on a recording material, comprising: a first housing; a second housing connected to the first housing in the vertical direction; a positioning shaft provided on the first housing; and a fitting portion provided on the second housing that fits with the positioning shaft, wherein when connecting the first housing and the second housing, the fitting portion is formed such that relative movement between the positioning shaft and the second housing is possible in a first direction intersecting the vertical direction, and the range of relative movement between the positioning shaft and the second housing is limited in a second direction intersecting the vertical direction and the first direction.

[0008] An image forming apparatus according to one embodiment of the present invention is an image forming apparatus for forming a toner image on a recording material, comprising: a first housing; a second housing connected to the first housing in the vertical direction; a positioning shaft provided on the first surface of the first housing; a fitting portion provided on the second surface of the second housing facing the first surface and fitting with the positioning shaft; a first projection provided on the first housing that protrudes from the first surface toward the second surface; and a second projection provided on the second housing that protrudes from the second surface toward the first surface, wherein when connecting the first housing and the second housing, the relative movement between the positioning shaft and the second housing in the first direction intersecting the vertical direction The fitting portion is formed in such a way that it enables the above, and limits the range of relative movement between the positioning shaft and the second housing in a second direction intersecting the vertical direction and the first direction, and when connecting the first housing and the second housing, the first projection and the second projection come into contact with the second housing with respect to the first direction, and the positioning shaft is not fitted into the fitting portion, and the first housing is in a second position downstream of the first position with respect to the second housing with respect to the first direction, the first projection and the second projection do not come into contact, and the positioning shaft is fitted into the fitting portion. [Effects of the Invention]

[0009] According to the present invention, it is possible for an operator to easily align the housings when stacking them vertically. [Brief explanation of the drawing]

[0010] [Figure 1] A schematic diagram showing the image forming apparatus of this embodiment. [Figure 2] A perspective view showing an image forming apparatus with the main unit and paper feeder separated. [Figure 3] (a) Perspective view showing the paper feed device as seen from above, (b) Perspective view showing the main body of the device as seen from below. [Figure 4] Enlarged view showing the positioning member. [Figure 5]A schematic diagram showing the positioning member, positioning shaft, and protrusion. [Figure 6] This diagram illustrates the alignment process, showing (a) the state before the alignment process, (b) the state during the alignment process, and (c) the state after the alignment process. [Figure 7] A side cross-sectional view showing the positioning axis and the position of the protrusion relative to the positioning member. [Figure 8] (a) A schematic diagram showing the state in which the protrusion of the main body of the device and the protrusion of the paper feeder are in contact, (b) A schematic diagram showing the state just before the contact between the protrusion of the main body of the device and the protrusion of the paper feeder is released, and (c) A schematic diagram showing the state in which the protrusion of the main body of the device and the protrusion of the paper feeder are not in contact. [Figure 9] A schematic diagram showing the positioning member, positioning shaft, and protrusion when the mounting direction is from front to back. [Figure 10] A schematic diagram showing a positioning member and positioning shaft in a configuration without protruding parts. [Modes for carrying out the invention]

[0011] <Image forming apparatus> The following describes this embodiment. First, the general configuration of the image forming apparatus 1 will be described using Figures 1 and 2. As shown in Figures 1 and 2, the image forming apparatus 1 of this embodiment is broadly divided into the apparatus body 100 and the paper feed device 150. The paper feed device 150 is an example of an optional device that is detachably disposed on the lower side of the apparatus body 100. As will be described in more detail later, the apparatus body 100 is disposed on top of the paper feed device 150 with the housing 100A of the paper feed device 150 aligned with the housing 150A of the paper feed device 150 in the front-to-back and left-to-right directions. That is, in this embodiment, the housing 100A and the housing 150A are connected in the vertical direction. The connection in this embodiment includes a state in which the two housings are fixed by welding or screws, or a state in which one housing is simply placed on top of the other housing. Hereinafter, for convenience, the housing 100A will be described as the first housing and the housing 150A as the second housing. However, if the arrangement of the positioning axis and positioning member described later is reversed, the housing 150A corresponds to the first housing and the housing 100A corresponds to the second housing.

[0012] In the following explanation, "front" and "back" refer to the front side of the image forming apparatus 1 and the back side, respectively. The front side of the image forming apparatus 1 is generally the side where the user is located when operating the image forming apparatus 1. For example, the side where the control panel is located, or the side from which the cassette 31 containing the recording material is pulled out, is the front side. "Right" and "left" correspond to the view of the image forming apparatus 1 from the front side. "Vertical direction" refers to the vertical direction when the image forming apparatus 1 is installed on the mounting surface. Generally, the "vertical direction" is the same as the vertical direction. Figure 1 shows the image forming apparatus 1 as viewed from the front side.

[0013] The image forming apparatus 1 shown in FIG. 1 is a full-color printer using an intermediate transfer system. In the apparatus main body 100 of the image forming apparatus 1, for example, a cassette 31, a conveyance path 60, an image forming unit 500, a fixing device 50, a discharge unit 700, a duplex conveyance path 701, various rollers, etc. are installed in the housing 100A. The image forming unit 500 forms a toner image on a recording material S based on an image signal received from an external terminal such as a document reading device (not shown) or a personal computer. The image forming unit 500 has four-color image forming units PY, PM, PC, PK for forming toner images of yellow (Y), magenta (M), cyan (C), and black (K), and an intermediate transfer body unit 600.

[0014] The conveyance process of the recording material S in the apparatus main body 100 will be described. The recording material S is accommodated in a form loaded in one or more (here, two) cassettes 31. The recording material S is fed one by one from the cassette 31 to the conveyance path 60 by the supply roller 31a in accordance with the image forming timing. In the present embodiment, the conveyance path 60 is provided so as to be able to convey the recording material S from below to above (so-called, vertical conveyance system). Examples of the recording material S include various types of sheet materials such as plain paper, thick paper, rough paper, embossed paper, coated paper, plastic film, cloth, etc.

[0015] The recording material S supplied from the cassette 31 to the conveyance path � is conveyed to a registration roller pair 42 disposed in the middle of the conveyance path 60. The registration roller pair 42 corrects the skew of the recording material S, and conveys the recording material S with the skew corrected to a secondary transfer nip portion formed by a secondary transfer inner roller 22 and a secondary transfer outer roller 44.

[0016] Regarding the conveyance process of the recording material S up to the above-described secondary transfer nip portion, the image forming process of the toner image sent to the secondary transfer nip portion at the same timing will be described. First, the image forming units PY to PK will be described. However, since the image forming units PY to PK of each color are basically the same except for the color of the toner, hereinafter, the yellow image forming unit PY will be described as a representative example.

[0017] The image forming unit PY includes a photosensitive drum 11Y, a charger 12Y, an exposure device 13Y, and a developing device 14Y. The surface of the rotatably driven photosensitive drum 11Y is uniformly charged in advance by the charger 12Y, and then an electrostatic latent image is formed by the laser light irradiated from the exposure device 13Y driven based on the image signal. Then, the electrostatic latent image formed on the photosensitive drum 11Y is developed into a toner image by the developing device 14Y. The developing device 14Y develops the electrostatic latent image into a toner image using a developer containing toner and carrier. The toner image developed on the photosensitive drum 11Y is given a primary transfer voltage by a primary transfer roller 25Y disposed opposite with the photosensitive drum 11Y and the intermediate transfer belt 21 interposed therebetween, and is primarily transferred from the photosensitive drum 11Y to the intermediate transfer belt 21.

[0018] The intermediate transfer belt 21 is an endless belt, and is stretched by a secondary transfer inner roller 22, a driving roller 23, a tension roller 24, etc. and moved in the direction of arrow A in the figure. The tension roller 24 rotates passively as the intermediate transfer belt 21 is moved by the driving roller 23 while applying tension to the intermediate transfer belt 21. The image forming processes for each color processed in parallel by the above-described image forming units PY to PK for each color are performed at a timing to sequentially overlap on the toner image of the color primarily transferred upstream in the moving direction on the intermediate transfer belt 21. As a result, finally, a full-color toner image is formed on the intermediate transfer belt 21. Note that the primary transfer rollers 25Y to 25K, the intermediate transfer belt 21, the secondary transfer inner roller 22, the driving roller 23, and the tension roller 24 are integrally configured as an intermediate transfer unit 600.

[0019] Based on the conveyance process and the image forming process described above, secondary transfer is performed in the secondary transfer nip portion where the timing of the recording material S and the full-color toner image coincides, and the toner image is transferred from the intermediate transfer belt 21 to the recording material S. By applying a predetermined pressing force and a secondary transfer voltage to the recording material S sandwiched and conveyed in the secondary transfer nip portion, the toner image is transferred from the intermediate transfer belt 21 onto the recording material S.

[0020] The recording material S onto which the toner image has been transferred is transported along the transport path 60 to the fuser 50, where the toner image is fixed to the recording material S by the application of heat and pressure. The fuser 50 has a fuser roller heated by a heater (not shown) and a pressure roller that contacts the fuser roller to form a fuser nip, and the toner image is fixed to the recording material S by applying heat and pressure to the recording material S as it passes through the fuser nip.

[0021] The recording material S, on which the toner image has been fixed by the fuser 50, is transported further upward along the transport path 60 and discharged to the outside by the discharge unit 700. The discharge unit 700 has a discharge roller 61, and the recording material S is discharged onto the discharge tray 81 by the discharge roller 61. In this embodiment, in the double-sided mode in which an image is formed on both sides of the recording material S, the recording material S is transported to the double-sided transport path 701 to reverse the recording surface in order to form an image on the back side of the recording material S on which an image has been formed on one side. In the double-sided mode, the recording material S is transported by the forward rotation of the discharge roller 61 until its rear end passes the flapper 63, and then the front and rear ends are reversed by the reverse rotation of the discharge roller 61 and the recording material S is transported to the double-sided transport path 701. The recording material S transported to the double-sided transport path 701 is returned to the registration roller pair 42. The subsequent transport and the image formation process on the back side are the same as in the above case and will not be described. The recording material S with images formed on both sides is discharged to the outside by the discharge unit 700.

[0022] <Paper feeder> In the paper feed device 150, a supply unit 300 having one or more (two in this case) cassettes 32 containing recording material S, a supply roller 32a, etc., is installed in the housing 150A. The recording material S is supplied one sheet at a time from the cassettes 32 to the transport path 60 of the main unit 100 by the supply roller 32a in accordance with the image formation timing. Subsequent operation is the same as described above.

[0023] The housing 100A of the main unit 100 and the housing 150A of the paper feed device 150 are each composed of a highly rigid metal frame, such as a front side plate provided on the front side, a rear side plate provided on the rear side, support columns that support them, and stays and beams that connect them, and are covered by multiple exterior covers that constitute the exterior of the image forming apparatus 1. The housing 150A is positioned below the housing 100A so as to be connectable.

[0024] As shown in Figure 2, the optional paper feeder 150 is detachably attached to the main unit 100. The paper feeder 150 has four casters 151 on its underside and is installed on a surface such as the floor. The paper feeder 150 also has four height-adjustable legs 152 on its underside, allowing the operator to adjust the height of the paper feeder 150 while the casters 151 are lifted away from the installation surface.

[0025] When connecting the main unit 100 to the paper feed device 150 set on the installation surface, two workers work together, each holding the handles 40 provided on both the left and right sides of the main unit 100, and lifting the main unit 100. The handles 40 are rotatably positioned to be stored in a storage compartment 41 on the side of the main unit 100 when not in use by the worker, and to protrude from the side of the main unit 100 as shown in Figure 2, making it easier for the worker to grip when in use. The workers then place the lifted main unit 100 on top of the paper feed device 150 and connect and fix the housing 100A and housing 150A using screws (not shown).

[0026] Here, since the main body 100 and the paper feeder 150 are separate structures, the main body 100 is connected to the paper feeder 150 after the relative positions of the housing 100A and housing 150A have been adjusted. If the housing 100A and housing 150A are misaligned from their predetermined positions, for example, the recording material S supplied from the paper feeder 150 to the transport path 60 may become excessively skewed, causing the recording material S to jam in the transport path 60, or the registration roller pair 42 may not be able to fully correct the skew of the recording material S, resulting in the toner image not being transferred to the correct location on the recording material S.

[0027] In this embodiment, a positioning shaft is provided on one of the housings 100A and 150A, and a positioning hole is provided on the other, so that an operator can align the housings 100A and 150A to predetermined positions. In the conventional case, in order for the operator to engage the positioning shaft and the positioning hole, the operator has to lift the heavy device body 100 and then align the housings 100A and 150A to predetermined positions. Such an operation is cumbersome.

[0028] In view of this, in this embodiment, the operator first temporarily places the device body 100 on the paper feed device 150. Then, the operator slides the temporarily placed device body 100 relative to the paper feed device 150. This method allows the housing 100A and housing 150A to be aligned to a predetermined position even without lifting the device body 100. The configuration of this embodiment that realizes this will be explained below with reference to Figures 3(a) to 7. Here, the left-right direction is the mounting direction of the device body 100 relative to the paper feed device 150 (first direction), and the front-back direction is the direction that intersects the vertical direction and the mounting direction (second direction). In the following example, the device body 100 is slid from left to right relative to the paper feed device 150. In this operation, the position of the device body 100 relative to the paper feed device 150 at the earlier point in time is sometimes called "upstream," and the position of the device body 100 relative to the paper feed device 150 at the later point in time is sometimes called "downstream." The terms "upstream" and "downstream" may also be used to refer to the components of the main body 100 and the components of the paper feed device 150, as appropriate.

[0029] Figure 3(a) is a perspective view showing the paper feed device 150 as seen from above. As shown in Figure 3(a), the paper feed device 150 has an upper front frame 160a and an upper rear frame 160b on its upper side, which constitute part of the frame of the housing 150A. The upper front frame 160a is positioned in front of the center in the front-to-back direction and spans the left and right frames, while the upper rear frame 160b is positioned in rear of the center in the front-to-back direction and spans the left and right frames. These upper front frame 160a and upper rear frame 160b have widths in the front-to-back direction to accommodate the protrusions 55a, 55b, 55c, and 55d provided on the device body 100, which will be described later.

[0030] On the upper surface (second surface) of the upper front frame 160a, positioning members 170a and 170b are provided at a distance from each other in the left-right direction, serving as fitting parts. Positioning shafts 50a and 50b (see Figure 3(b)) provided on the device body 100 are fitted into the positioning members 170a and 170b, respectively. Specifically, each of the positioning members 170a and 170b has a groove that extends in the mounting direction. The positioning shafts 50a and 50b are fitted into these grooves. An opening is provided at one end of the groove on the upstream side in the mounting direction so that the positioning shafts 50a and 50b can enter the groove when connecting the device body 100 and the paper feed device 150. The positioning members 170a and 170b will be described in detail later (see Figure 4).

[0031] Figure 3(b) is a perspective view showing the main body of the device 100 as seen from the bottom. As shown in Figure 3(b), the main body of the device 100 has a bottom front frame 52a and a bottom rear frame 52b on its bottom side, which constitute part of the frame of the housing 100A. The bottom front frame 52a is spanned across the left and right frames at the front in the front-to-back direction, and the bottom rear frame 52b is spanned across the left and right frames at the rear in the front-to-back direction. These bottom front frame 52a and bottom rear frame 52b are positioned opposite the top front frame 160a and top rear frame 160b of the housing 100A, respectively, when the main body of the device 100 is mounted on the paper feed device 150.

[0032] On the lower surface (first surface) of the lower front frame 52a, positioning shafts 50a and 50b for fitting with positioning members 170a and 170b are provided at positions spaced apart in the left-right direction. The positioning shafts 50a and 50b are, for example, cylindrical protruding members that project downward from the lower surface of the lower front frame 52a. Also on the lower surface of the lower front frame 52a, protruding portions 55a and 55b are provided in the left-right direction, aligned with the positioning shafts 50a and 50b, and project toward the upper front frame 160a below. The protruding portions 55a and 55b are provided upstream of the positioning shafts 50a and 50b with respect to the mounting direction of the device body 100 to the paper feed device 150 (in this case, from left to right). When the device body 100 is temporarily placed on the paper feed device 150, the protruding portions 55a and 55b abut against the upper surface of the upper front frame 160a of the paper feed device 150.

[0033] On the other hand, on the lower surface of the lower rear frame 52b, similar to the above-described protrusions 55a and 55b, protrusions 55c and 55d are provided at intervals in the left-right direction, projecting toward the lower upper rear frame 160b. The protrusions 55c and 55d contact the upper surface of the upper rear frame 160b of the paper feed device 150 when the device body 100 is temporarily placed on the paper feed device 150. These protrusions 55a, 55b, 55c, and 55d are made of a highly rigid metal or the like that does not deform due to the weight of the device body 100 when in contact with the upper front frame 160a and the upper rear frame 160b. It is preferable to provide three or more of these support protrusions 55a, 55b, 55c, and 55d in order to support the device body 100, which is temporarily placed on the paper feed device 150, so that it can slide without tilting. The configurations of the protruding parts 55a, 55b, 55c, and 55d are examples of support structures, and the support structure between the device body 100 and the paper feed device 150 is not limited to these. When the device body 100 is temporarily placed on the paper feed device 150, the positioning shafts 50a and 50b do not come into contact with the surface of the upper front frame 160a. That is, the lower ends of the positioning shafts 50a and 50b in the vertical direction (the tips in the protruding direction) are spaced apart from the surface of the upper front frame 160a.

[0034] <Positioning component> The positioning members 170a and 170b will now be described. Figure 4 is an enlarged view showing the positioning members 170a and 170b. Figure 5 is a schematic diagram showing the positions of the positioning members 170a and 170b, the positioning axes 50a and 50b, and the protrusions 55a to 55d when the device body 100 is mounted on the paper feed device 150. Note that the positioning members 170a and 170b may have the same configuration, so the following description will use the positioning member 170b located on the left side of the upper front frame 160a as an example.

[0035] The positioning member 170b is formed so that the positioning axis 50b can enter along the mounting direction (here, the direction from left to right, the entry direction). As shown in Figure 4, the positioning member 170b has a stopper wall portion 180, a top plate portion 181, a rear wall portion 182, and a front wall portion 183. The positioning member 170b is arranged so as to traverse the upper surface of the upper front frame 160a in the front-rear direction, such that the stopper wall portion 180 is positioned on the downstream side in the mounting direction. The rear wall portion 182 and the front wall portion 183 extend from the stopper wall portion 180 to the upstream side (left side) in the mounting direction. The rear wall portion 182 and the front wall portion 183 are positioned opposite each other with a gap between them at both ends of the stopper wall portion 180 in the front-rear direction. The top plate portion 181 is positioned at the upper ends of the stopper wall portion 180, the rear wall portion 182, and the front wall portion 183. The top plate portion 181 has a notch 184 into which the positioning shaft 50b (see Figure 3(b)) of the device body 100 enters when the device body 100 is attached to the paper feed device 150. A stopper wall portion 180 is located downstream of the notch 184 in the attachment direction. On the other hand, the upstream side of the notch 184 in the attachment direction is open to allow the positioning shaft 50b to enter.

[0036] As shown in Figure 5, a notch 184 is provided in the top plate portion 181, so that the top plate portion 181 forms a guide portion 181a and a positioning groove portion 181b. When connecting the device body 100 and the paper feed device 150, the positioning shaft 50b moves relative to the paper feed device 150 in the mounting direction from left to right. The guide portion 181a restricts the movement of the moving positioning shaft 50b in the direction intersecting the mounting direction (front-back direction). Specifically, the width of the guide portion 181a in the front-back direction narrows as it moves from upstream to downstream in the mounting direction. With this configuration, the guide portion 181a guides the positioning shaft 50b so that it can enter the positioning groove portion 181b. An opening is provided at the upstream end of the positioning groove portion 181b in the mounting direction (the left end in the left-right direction, and the second end on the opposite side). The positioning shaft 50b enters the positioning groove portion 181b through this opening. The downstream end of the positioning groove 181b in the mounting direction (the right end in the left-right direction, the first end) is closed. The width of the positioning groove 181b in the front-rear direction (the distance in the front-rear direction) is approximately constant.

[0037] Thus, the top plate portion 181 has a guide portion 181a on the upstream side in the mounting direction and a positioning groove portion 181b continuous with the guide portion 181a on the downstream side in the mounting direction. The spacing of the positioning groove portions 181b in the front-rear direction is formed to a constant width that is approximately the same as the diameter of the positioning shaft 50b. Therefore, when the positioning shaft 50b is fitted into the positioning groove portion 181b, the range of relative movement of the positioning shaft 50b with respect to the paper feed device 150 in the direction intersecting the mounting direction (front-rear direction) is limited. In addition, the downstream end of the positioning groove portion 181b in the mounting direction (right end in the left-right direction) is closed. Therefore, when the positioning shaft 50b abuts against this closed end of the positioning groove portion 181b, the range of relative movement of the positioning shaft 50b with respect to the paper feed device 150 in the mounting direction (left-right direction) is limited.

[0038] Next, the alignment of the housing 100A of the main unit 100 and the housing 150A of the paper feed device 150 will be explained using Figures 6(a) to 6(c) with reference to Figures 3, 4, and 5. Figure 6(a) shows the state before the alignment work by the operator, Figure 6(b) shows the state during the alignment work by the operator, and Figure 6(c) shows the state after the alignment work by the operator.

[0039] As shown in Figure 6(a), the operator first grasps the handle 40 and lifts the device body 100, then moves the lifted device body 100 above the paper feed device 150. Then, the operator lowers the device body 100 toward the paper feed device 150. At this time, as shown in Figure 6(b), the device body 100 is temporarily placed in a position shifted to the left of its original mounting position relative to the paper feed device 150. In this embodiment, the housings 100A and 150A are temporarily placed in a shifted state such that the right side of the device body 100 overlaps the projection plane of the paper feed device 150 when viewed from above. This is suitable when the heavier discharge unit 700 and double-sided transport path 701 are installed vertically on the right side of the housing 100A (see Figure 1), and the center of gravity of the device body 100 tends to shift to the right. In other words, the operator can temporarily place the relatively heavier right side of the device body 100 onto the paper feed device 150 first.

[0040] When the device body 100 is temporarily placed on the paper feed device 150, the protrusions 55a, 55b, 55c, and 55d of the device body 100 are placed on the upper front frame 160a and upper rear frame 160b of the paper feed device 150, respectively. The protrusions 55a and 55b are placed on the upper front frame 160a upstream of the positioning members 170a and 170b in the mounting direction. Thus, in this embodiment, the upper front frame 160a and upper rear frame 160b have contact surfaces for temporarily placing the protrusions 55a, 55b, 55c, and 55d.

[0041] As shown in Figure 6(b), when the device body 100 is temporarily placed, the positioning shafts 50a and 50b are not fitted to the positioning members 170a and 170b. Therefore, in order to fit the positioning shafts 50a and 50b to the positioning members 170a and 170b, the operator slides the device body 100 from left to right while it is still temporarily placed on the paper feed device 150, that is, while the protrusions 55a, 55b, 55c, and 55d are in contact with the upper front frame 160a and the upper rear frame 160b.

[0042] As the main body of the device 100 slides, the positioning shafts 50a and 50b enter the notches 184 of the positioning members 170a and 170b. More precisely, the positioning shafts 50a and 50b first enter the guide portion 181a of the notch 184. The main body of the device 100 slides from left to right, with its movement in the front-rear direction restricted by the notches 184 of the positioning members 170a and 170b via the positioning shafts 50a and 50b. As described above, in the positioning members 170a and 170b, the front-rear width of the guide portion 181a of the top plate portion 181 gradually narrows from the upstream side to the downstream side in the mounting direction (see Figure 5). As a result, even if there is some variation in the front-to-back relative positions of the positioning axes 50a and 50b with respect to the positioning members 170a and 170b when the device body 100 is temporarily placed, the operator can easily insert the positioning axes 50a and 50b into the notches 184 of the positioning members 170a and 170b.

[0043] The positioning shafts 50a and 50b are first guided by the guide portion 181a of the notch portion 184 and reach the opening of the positioning groove portion 181b. Then, the positioning shafts 50a and 50b move along the groove portion 181b. The device body 100 is then slid until the positioning shafts 50a and 50b abut against the abutment wall portion 180 (closed end of the positioning groove portion 181b) of the positioning members 170a and 170b, respectively. As the positioning shafts 50a and 50b abut against the abutment wall portion 180 of the positioning members 170a and 170b, respectively, the housings 100A and 150A are aligned at the position shown in Figure 6(c). After the housings 100A and 150A are aligned, the operator fixes the housing 100A to the housing 150A with screws (not shown) or the like.

[0044] In this embodiment, two positioning members 170a and 170b are provided. To align the housing 100A and the housing 150A, at least one pair of positioning shafts 50a and positioning members 170a are sufficient. Positioning member 170b may be omitted. Positioning member 170b, provided on the upstream side in the mounting direction, also functions as a rotation restricting member that prevents the housing 100A from rotating relative to the housing 150A around the positioning shaft 50a fitted to the positioning member 170a provided on the downstream side in the mounting direction when the device body 100 is mounted on the paper feed device 150. In this way, the addition of positioning member 170b makes it easy to align the housing 100A and the housing 150A in the rotational direction.

[0045] As shown in Figure 7, the positioning shaft 50b is provided so as to protrude toward the upper front frame 160a from the lower surface (first surface) of the lower front frame 52a that faces the upper front frame 160a. The positioning member 170b is provided on the upper surface (second surface) of the upper front frame 160a that faces the lower surface of the lower front frame 52a, at a position closer to the lower surface of the lower front frame 52a than to the upper surface of the upper front frame 160a. When the positioning shaft 50b is in contact with the abutment wall portion 180, it is preferable that a portion of the protruding portion 55b enters the notch portion 184 of the positioning member 170b, or in other words, when viewed in the front-rear direction, a portion of the protruding portion 55b on the downstream side in the mounting direction overlaps with the guide portion 181a of the top plate portion 181. If an unintended large force is applied to the main body 100 in the front-rear direction before the housing 100A is fixed to the housing 150A with screws or the like, there is a risk that the positioning shaft 50b (50a) may break. Therefore, a part of the protruding portion 55b (55a) is made to enter the notch portion 184 to prevent the positioning shaft 50b (50a) from breaking.

[0046] As described above, in this embodiment, positioning members 170a and 170b are provided on the housing 150A of the paper feed device 150, and positioning shafts 50a and 50b are provided on the housing 100A of the device body 100. The positioning members 170a and 170b are formed such that, with respect to the direction in which the device body 100 is mounted to the paper feed device 150, the positioning shafts 50a and 50b enter and fit into them as the device body 100 is slid into the paper feed device 150. When the positioning shafts 50a and 50b fit into the positioning members 170a and 170b, respectively, the housings 100A and 150A are aligned. In other words, when attaching the main unit 100 and the paper feed device 150, the operator can temporarily place the main unit 100 on the paper feed device 150, and then slide the main unit 100 onto the paper feed device 150 while it is temporarily placed there, thereby easily aligning the housing 100A and the housing 150A. As a result, the operator does not have to keep the main unit 100 lifted by temporarily placing it on the paper feed device 150, thus reducing the burden of attaching the main unit 100, and more specifically, the burden of aligning the housing 100A and the housing 150A.

[0047] The guide portion 181a in the above-described embodiment may be omitted. By engaging the positioning shaft 50b with the positioning groove portion 181b, the degree of freedom of relative movement of the positioning shaft 50b with respect to the paper feed device 150 (housing 150A) is restricted. Specifically, in the first direction intersecting the vertical direction (the left-right direction in the above example), relative movement of the positioning shaft 50b with respect to the paper feed device 150 (housing 150A) is permitted. On the other hand, in the second direction intersecting both the vertical direction and the first direction (the front-back direction in the above example), the range of relative movement of the positioning shaft 50b with respect to the paper feed device 150 (housing 150A) is restricted. With this configuration, the effect of reducing the burden on aligning the housing 100A and housing 150A as described above can be sufficiently obtained. It is conceivable that the absence of the guide portion 181a may cause some difficulty in getting the positioning shaft 50b into the positioning groove portion 181b. However, since this operation is performed by sliding the main body of the device 100 onto the paper feed device 150 while it is temporarily in place, it is still easier to align the device compared to conventional technology.

[0048] In the above-described embodiment, although not shown in the illustration, it is preferable that a height adjustment member similar to the height adjustment leg 152 of the paper feed device 150 (see Figure 2) be detachably provided on the underside of the device body 100. When the operator uses the device body 100 alone, the operator attaches the height adjustment members to the four corners of the underside of the device body 100. The operator then adjusts the height of the underside of the device body 100 from the installation surface using the height adjustment members so that the positioning shafts 50a, 50b and the protrusions 55a to 55d do not come into contact with the installation surface.

[0049] In the above-described embodiment, positioning members 170a and 170b are provided on the housing 150A of the paper feed device 150, and positioning shafts 50a and 50b and protrusions 55a to 55d are provided on the housing 100A of the device body 100, but the invention is not limited to this. Positioning members 170a and 170b may be provided on the housing 100A of the device body 100, and positioning shafts 50a and 50b and protrusions 55a to 55d may be provided on the housing 150A of the paper feed device 150.

[0050] <Other Embodiments> In the embodiments described above, for example, as shown in Figure 3(a) and Figure 7, the upper surfaces of the upper front frame 160a and the upper rear frame 160b that abut the protrusions 55a, 55b, 55c, and 55d are formed in a planar shape, but this is not limited to this. The upper surfaces of the upper front frame 160a and the upper rear frame 160b do not have to be planar, and may have protrusions 1601 formed on them, for example, as shown in Figures 8(a) to 8(c). Figures 8(a) to 8(c) show a protrusion 1601 (second protrusion) formed on the upper surface of the upper front frame 160a, corresponding to the protrusion 55b (first protrusion) of the lower front frame 52a.

[0051] The protrusion 55b is provided on the lower front frame 52a and protrudes from the lower surface of the lower front frame 52a toward the upper surface of the upper front frame 160a. The protrusion 1601 is provided on the upper front frame 160a and protrudes from the upper surface of the upper front frame 160a toward the lower surface of the lower front frame 52a. Although not shown in the figures, in addition to the protrusion 1601, another protrusion corresponding to the protrusion 55a of the lower front frame 52a is formed on the upper surface of the upper front frame 160a in the same way as the protrusion 1601.

[0052] When the main body 100 is temporarily placed on the paper feed device 150, and the housing 100A is in a first position relative to the housing 150A in the mounting direction, as shown in Figure 8(a), the protrusion 55b is in contact with the protrusion 1601, which is one level higher than the upper surface of the upper front frame 160a. However, the positioning shaft 50b is not fitted into the positioning member 170b. When the main body 100, which is temporarily placed on the paper feed device 150, is slid from left to right, the main body 100 falls to the paper feed device 150 side, after passing through a state just before the contact between the protrusion 55b and the protrusion 1601 is released, as shown in Figure 8(b). When the housing 100A is in a second position downstream of the first position relative to the housing 150A in the mounting direction, as shown in Figure 8(c), the protrusion 55b and the protrusion 1601 are not in contact, but the positioning shaft 50b is fitted into the positioning member 170b.

[0053] The positioning member 170b has a stopper member 190 as a limiting member, and the stopper member 190 is located upstream of the abutment wall 180 in the mounting direction, leaving a gap between it and the abutment wall 180 into which the positioning shaft 50b can be fitted. When the device body 100 falls towards the paper feed device 150, the positioning shaft 50b enters the space between the stopper member 190 and the abutment wall 180 from the upper left. With the positioning shaft 50b in contact with the abutment wall 180, its movement in the mounting direction is restricted by the abutment wall 180, and its movement in the opposite direction (from right to left in this case) is restricted by the stopper member 190. Also, with the protrusion 55b not in contact with the protrusion 1601, its movement in the opposite direction to the mounting direction is restricted by the protrusion 1601. As a result, even if an unintended large force is applied to the main body 100 in the left-right direction before the housing 100A is fixed to the housing 150A with screws or the like, the aligned housings 100A and 150A will not become misaligned.

[0054] In the above-described embodiment, as shown in Figures 3(a) and 3(b), the positioning members 170a and 170b are provided on the upper front frame 160a, the positioning shafts 50a and 50b and the protrusions 55a and 55b are provided on the lower front frame 52a, and the protrusions 55c and 55d are provided on the lower rear frame 52b. This is an example where the mounting direction of the device body 100 to the paper feed device 150 is "left to right," as described above. In contrast, if, for example, a drive unit or electrical components (not shown) that are heavier than the rest are installed on the rear side of the housing 100A, it is preferable to mount the device body 100 to the paper feed device 150 from "front to back." Figure 9 is a schematic diagram showing the positioning members 170a and 170b, positioning shafts 50a and 50b, and the protrusions 55a, 55b, 55c, and 55d when the mounting direction is "front to back."

[0055] When the mounting direction of the main body 100 to the paper feed device 150 is "front to back", as shown in Figure 9, the positioning members 170a and 170b are provided on the surface of the upper right frame 160d of the housing 150A. In contrast, the positioning shafts 50a and 50b and the protrusions 55a and 55b are provided on the surface of the lower right frame (not shown) of the housing 100A. Also, the protrusions 55c and 55d are provided on the surface of the lower left frame (not shown) of the housing 100A.

[0056] The paper feeder 150 has an upper right frame 160d and an upper left frame 160c on its upper side, which form part of the frame of the housing 150A. The upper right frame 160d is to the right of the center in the left-right direction and spans the front and rear frames, and the upper left frame 160c is to the left of the center in the left-right direction and spans the front and rear frames. Although not shown in the illustration, the main body of the device 100 has a lower right frame and a lower left frame on its lower side, which form part of the frame of the housing 100A. The lower right frame is to the right of the front and rear frames in the left-right direction and spans the front and rear frames, and the lower left frame is to the left of the left-right direction and spans the front and rear frames. These lower right and lower left frames are positioned opposite the upper right frame 160d and upper left frame 160c of the paper feeder 150, respectively, when the main body of the device 100 is mounted on the paper feeder 150.

[0057] When the mounting direction of the main unit 100 is "front to back", the housings 100A and 150A are temporarily placed offset from each other so that, when viewed from above, the rear of the main unit 100 aligns with the projection plane of the paper feed device 150. This is suitable when a heavier drive unit or electrical components (not shown) are installed on the rear of housing 100A, causing the center of gravity of the main unit 100 to shift towards the rear.

[0058] When the device body 100 is temporarily placed, the positioning shafts 50a and 50b are not fitted into the positioning members 170a and 170b. Therefore, in order to fit the positioning shafts 50a and 50b into the positioning members 170a and 170b, the operator slides the device body 100 from front to back while it is temporarily placed on the paper feed device 150, that is, while the protruding parts 55a, 55b, 55c, and 55d are in contact with the upper right frame 160d and the upper left frame 160c. As the device body 100 slides, the positioning shafts 50a and 50b enter the notches 184 of the positioning members 170a and 170b.

[0059] In the example shown in Figure 9, the main body of the device 100 is slid until the positioning shaft 50a abuts against the abutment wall portion 180 of the positioning member 170a. The housing 100A and the housing 150A are aligned when the positioning shaft 50a abuts against and fits into the abutment wall portion 180 of the positioning member 170a. Note that the positioning shaft 50b does not have to abut against the abutment wall portion 180 of the positioning member 170b. That is, the positioning shaft 50a may be in contact with one end of the positioning groove portion 181b of the positioning member 170a, while the positioning shaft 50b is spaced apart from both ends of the positioning groove portion 181b of the positioning member 170b (one end has an opening and the other end is closed). The positioning member 170b should be able to restrict the rotation of the housing 100A relative to the housing 150A around the positioning shaft 50a fitted to the positioning member 170a, when the device body 100 is mounted on the paper feed device 150.

[0060] In the embodiment described above, a configuration with protrusions 55a, 55b, 55c, and 55d is shown, but in some cases, a configuration without protrusions 55a, 55b, 55c, and 55d may be used. Figure 10 is a schematic diagram showing the positioning members 170a, 170b, and 170c and the positioning axes 50a, 50b, and 50c in a configuration without protrusions. The explanation will be given using Figure 10 with reference to Figures 3(a) and 3(b). The mounting direction of the device body 100 is "from left to right".

[0061] Positioning members 170a and 170b are provided on the upper front frame 160a of the housing 150A, as in the embodiment described above. In addition, a separate positioning member 170c is provided on the upper rear frame 160b of the housing 150A, as shown in Figure 10. These positioning members 170a, 170b, and 170c are made of a highly rigid metal or the like. Positioning shafts 50a and 50b are provided on the lower front frame 52a of the housing 100A, as in the embodiment described above. A positioning shaft 50c for fitting with the positioning member 170c is provided on the lower rear frame 52b. These lower front frame 52a and lower rear frame 52b are not provided with protrusions 55a, 55b, 55c, and 55d.

[0062] If the protrusions 55a, 55b, 55c, and 55d are not provided, when the device body 100 is temporarily placed on the paper feed device 150, the lower front frame 52a is placed on the top plate portion 181 of the positioning members 170a and 170b, and the lower rear frame 52b is placed on the top plate portion 181 of the positioning member 170c. The operator slides the device body 100 from left to right while it is temporarily placed on the paper feed device 150, that is, while the top plate portions 181 of the positioning members 170a, 170b, and 170c are in contact with the lower front frame 52a and the lower rear frame 52b, in order to fit the positioning shafts 50a, 50b, and 50c onto the positioning members 170a, 170b, and 170c. In this case, the top plate portion 181 of the positioning members 170a, 170b, and 170c abuts against the lower surface of the lower front frame 52a and the lower surface of the lower rear frame 52b, respectively, becoming a support surface capable of supporting the housing 100A on the housing 150A. Then, as the device body 100 slides, the positioning shafts 50a, 50b, and 50c enter and fit into the notches 184 of the positioning members 170a, 170b, and 170c, thereby aligning the housing 100A and the housing 150A.

[0063] Furthermore, it is preferable to provide three or more positioning members 170a, 170b, and 170c in order to support the temporarily placed device body 100 so that it can slide without tilting. When three are provided as described above, it is preferable that the positioning member 170c is positioned between the positioning member 170a and the positioning member 170b in the left-right direction when viewed from the front.

[0064] In the above-described embodiment, the case in which the main unit 100 and the paper feeder 150 are mounted stacked vertically was used as an example. If there are three or more structures, the same effect can be obtained by applying the above-described embodiment to each structure that is in a relationship of being mounted stacked vertically. For example, it can also be applied when a document reading device is detachably installed above the main unit 100. [Explanation of Symbols]

[0065] 1…Image forming apparatus, 50a, 50b…Positioning axis, 52a…Frame (bottom front frame), 55a, 55b, 55c, 55d…Support part (protruding part), 100A…First housing (housing), 150A…Second housing (housing), 160a…Frame (top front frame), 170a, 170b…Fitting part (positioning member), 181…Support surface (top plate part), 181a…Guide part, 181b…Groove part (positioning groove part), 184…Notch part, 190…Restricting member (stopper member), 1601…Second protruding part (protruding part), S…Recording material

Claims

1. An image forming apparatus for forming an image on a recording material, The first enclosure and A second housing connected to the first housing in the vertical direction, A positioning shaft provided in the first housing, The second housing is provided with a fitting portion that engages with the positioning shaft, When connecting the first housing and the second housing, the fitting portion is formed such that relative movement between the positioning axis and the second housing is possible in a first direction intersecting the vertical direction, while limiting the range of relative movement between the positioning axis and the second housing in a second direction intersecting the vertical direction and the first direction. An image forming apparatus characterized by the following:

2. The fitting portion extends in the first direction and has a groove into which the positioning shaft is inserted. The image forming apparatus according to feature 1.

3. The positioning shaft abuts against one end of the groove in the first direction, thereby limiting the range of relative movement between the positioning shaft and the second housing in the first direction. The image forming apparatus according to feature 2.

4. An opening is provided at one end of the groove in the first direction for the positioning shaft to enter the groove along the first direction when connecting the first housing and the second housing. The image forming apparatus according to feature 2.

5. The positioning shaft abuts against the first end of the groove in the first direction, thereby limiting the range of relative movement between the positioning shaft and the second housing in the first direction. An opening is provided at the second end of the groove, opposite to the first end in the first direction, for the positioning shaft to enter the groove along the first direction when connecting the first housing and the second housing. The image forming apparatus according to feature 2.

6. When connecting the first housing and the second housing, the system further includes a guide portion that guides the positioning shaft to the opening of the groove portion by restricting the relative position to the second housing in the second direction. The image forming apparatus according to feature 5.

7. The spacing of the guide portion in the second direction narrows from the upstream side to the downstream side along the direction in which the positioning shaft enters when connecting the first housing and the second housing. The image forming apparatus according to feature 6.

8. A second positioning axis provided in the first housing, The second housing is further provided with a second fitting portion that engages with the second positioning shaft, When connecting the first housing and the second housing, the second fitting portion is configured to allow relative movement between the second positioning axis and the second housing in the first direction, while limiting the range of relative movement between the second positioning axis and the second housing in the second direction. The image forming apparatus according to feature 1.

9. The fitting portion extends in the first direction and has a first groove into which the positioning shaft is inserted. The second fitting portion extends in the first direction and has a second groove into which the second positioning shaft is inserted. By the positioning shaft contacting one end of the first groove in the first direction, the fitting portion limits the range of relative movement between the positioning shaft and the second housing in the first direction. In the state in which the positioning shaft is in contact with one end of the first groove, the second positioning shaft is located at a position spaced apart from both ends of the second groove in the first direction. The image forming apparatus according to feature 8.

10. The positioning shaft protrudes toward the second housing from the first surface of the first housing facing the second housing, The fitting portion is provided on the second surface of the second housing that faces the first surface, at a position closer to the first surface than the second surface. The image forming apparatus according to feature 1.

11. The first housing and the second housing are provided with a support portion that is in contact with the other of the first housing and the second housing, The positioning shaft protrudes toward the second housing from the first surface of the first housing facing the second housing, The tip of the positioning shaft in the protruding direction is spaced apart from the second surface of the second housing that is opposite to the first surface. The image forming apparatus according to feature 1.

12. The positioning shaft protrudes toward the second housing from the first surface of the first housing facing the second housing, The fitting portion has a support surface that contacts the first surface and is capable of supporting the first housing on the second housing. The image forming apparatus according to feature 1.

13. The first housing is connected to the second housing in the vertical direction. The image forming apparatus according to feature 1.

14. The first housing is connected vertically to the bottom of the second housing, The image forming apparatus according to feature 1.

15. An image forming apparatus for forming a toner image on a recording material, The first enclosure and A second housing connected to the first housing in the vertical direction, A positioning shaft provided on the first surface of the first housing, A fitting portion is provided on the second surface of the second housing facing the first surface, which engages with the positioning shaft, A first protrusion is provided on the first housing and protrudes from the first surface toward the second surface, The second housing is provided with a second projection that protrudes toward the first surface from the second surface, When connecting the first housing and the second housing, the fitting portion is formed such that relative movement between the positioning axis and the second housing is possible in a first direction intersecting the vertical direction, while limiting the range of relative movement between the positioning axis and the second housing in a second direction intersecting the vertical direction and the first direction. When connecting the first enclosure and the second enclosure, When the first housing is in a first position relative to the second housing with respect to the first direction, the first projection and the second projection are in contact, and the positioning shaft is not fitted into the fitting portion. When the first housing is in a second position downstream of the first position relative to the second housing in the first direction, the first projection and the second projection do not come into contact, and the positioning shaft fits into the fitting portion. An image forming apparatus characterized by the following:

16. The fitting portion has a limiting member that restricts the movement of the positioning shaft in the direction opposite to the first direction when the first housing is in the second position and the positioning shaft is fitted into the fitting portion. The image forming apparatus according to feature 15.

17. The fitting portion extends in the first direction and has a groove into which the positioning shaft is inserted. The positioning shaft abuts against the first end of the groove in the first direction, thereby limiting the range of relative movement between the positioning shaft and the second housing in the first direction. An opening is provided at the second end of the groove, opposite to the first end in the first direction, for the positioning shaft to enter the groove along the first direction when connecting the first housing and the second housing. The image forming apparatus according to feature 15.

18. When connecting the first housing and the second housing, the system further includes a guide portion that guides the positioning shaft to the opening of the groove portion by restricting the relative position to the second housing in the second direction. The image forming apparatus according to feature 17.

19. The spacing of the guide portion in the second direction narrows from the upstream side to the downstream side along the direction in which the positioning shaft enters when connecting the first housing and the second housing. The image forming apparatus according to feature 18.

Images